Search PubMedSearch

Biomedical subjects

R B Nussenblatt

Publications and source records attributed to R B Nussenblatt.

At least 19 recordsLinked to original sources

Periocular inflammation in mice with experimental systemic lupus erythematosus. A new experimental blepharitis and its modulation.

Experimental systemic lupus erythematosus (SLE) can be induced in mice by immunization with a human monoclonal anti-DNA Ab, bearing a major Id 16/6Id. Immunized mice initially produce Abs to 16/6Id, DNA and nuclear Ags, and subsequently develop various clinical manifestations including leukopenia and renal immune complex disease. MHC class I Ags play a critical role in the induction and progression of experimental SLE. The present study reports that ocular changes also occur in mice with experimental SLE. The ocular disease is characterized by bilateral subacute and chronic inflammation of the eyelids (blepharitis) with immune complex IgG deposition and hypertrophic meibomian glands. The severity of ocular changes was strain dependent: most severe in 129 mice, less intense in BALB/c animals and only minimal in C3H.SW mice. No blepharitis developed in mice deficient in MHC class I expression. Further, the disease was strongly inhibited in BALB/c mice treated with methimazole, an agent that has been shown to repress transcription of MHC class I. In these cases, there was no IgG deposition and a decreased infiltration of inflammatory cells in the eyelids. These observations thus suggest that, similar to the observation with experimental SLE, MHC class I is critical in the onset of this experimental autoimmune blepharitis. The new experimental eye disease described here provides an animal model for chronic blepharitis in humans, a common condition for which such a model has been sought.

Animals

Synergistic effect of rapamycin and cyclosporin A in the treatment of experimental autoimmune uveoretinitis.

Immunosuppressive drugs currently available for the treatment of autoimmune diseases display a narrow therapeutic window between efficacy and toxic side effects. The use of combinations of drugs that have a synergistic effect may expand this window and reduce the risk of toxicity. We evaluated the combination effect of rapamycin (Rapa) and cyclosporin A (CsA) in an autoimmune disease model of the eye. The dose-effect relationship of Rapa with CsA was measured in vitro on the inhibition of proliferation of retinal S-Ag-primed lymphocytes. A median effect analysis was performed and a combination index (CI) calculated for 50% inhibition of proliferation. Rapa and CsA were markedly synergistic over a wide dose range (lowest CI = 0.31). Calculated dose reduction factors indicated that Rapa could be reduced nine-fold and CsA reduced five-fold when these drugs were used in combination. These reduced doses were tested in vivo for the treatment of experimental autoimmune uveoretinitis (EAU). Twelve of 15 rats treated with CsA, 2 mg/kg/day, developed EAU with a median severity of 2.5. Fourteen of 15 rats treated with Rapa, 0.01 mg/kg/day, developed EAU with a median severity of 3.25. Complete inhibition of EAU was achieved in all 15 animals treated with the combination of Rapa and CsA (combined vs CsA alone, p < 0.0002; combined vs Rapa alone, p < 0.00001). The demonstrated synergistic relationship between Rapa and CsA will allow the use of reduced doses of each drug to achieve a therapeutic effect. The use of lower doses may reduce the toxicity of these drugs for the treatment of autoimmune uveitis.

Animals

32 cases of sympathetic ophthalmia. A retrospective study at the National Eye Institute, Bethesda, Md., from 1982 to 1992.

OBJECTIVE: To examine the relationship between visual outcome and the clinical management of patients with sympathetic ophthalmia. METHODS: Thirty-two patients with sympathetic ophthalmia who were seen at the National Eye Institute, Bethesda, Md, between 1982 and 1992, were retrospectively reviewed. RESULTS: There were equal numbers of males and females. Sympathetic ophthalmia occurred after trauma in 23 patients and surgery in nine patients. Sixteen of the 32 patients had a final visual acuity of 20/40 or better; 10 patients had a visual acuity worse than 20/200. Good visual outcome was associated with early and aggressive treatment with corticosteroids, sometimes in combination with other immunosuppressive agents. Poor visual acuity was associated with glaucoma, chorioretinal scars in the macula, and persistent uncontrolled inflammation. CONCLUSION: Prompt and aggressive use of antiinflammatory therapy can improve the visual outcome of patients with sympathetic ophthalmia.

Adolescent

Interleukin-10 in the vitreous of patients with primary intraocular lymphoma.

PURPOSE: To find an accurate and simple method to diagnose primary intraocular lymphoma. METHODS: We prospectively analyzed concentrations of interleukin-10, interleukin-1, interleukin-2, interleukin-4, and interleukin-6 in vitrectomy specimens from three patients with primary intraocular lymphoma and five patients with uveitis by enzyme-linked immunosorbent assay. RESULTS: Interleukin-10 in the vitreous was detected in patients with primary intraocular lymphoma. Interleukin-10 levels correlated with clinical activity and the number of malignant cells. CONCLUSION: Concentrations of interleukin-10 in the vitreous may be a helpful clue to both clinicians and pathologists in diagnosing primary intraocular lymphoma.

Enzyme-Linked Immunosorbent Assay

Monoclonal antibodies against CD54 (ICAM-1) and CD11a (LFA-1) prevent and inhibit endotoxin-induced uveitis.

We studied the effect of monoclonal antibodies (mAbs) against CD54 (intercellular adhesion molecule-1; ICAM-1) and CD11a (lymphocyte function-associated antigen-1; LFA-1) on the prevention and treatment of endotoxin-induced uveitis (EIU). When treated at the time of endotoxin injection the mean number of inflammatory cells infiltrating the eye +/- S.E.M. on histologic sections was 469.2 +/- 51.9 for controls, 13.8 +/- 2.6 for rats receiving anti-ICAM-1 mAb (P < 0.0001), and 195.8 +/- 48.8 for rats receiving anti-LFA-1 mAb (P = 0.0003). When treated after the start of inflammatory disease, the mean number of infiltrating inflammatory cells +/- S.E.M. was 273.0 +/- 30.7 for controls, 6.4 +/- 1.7 for rats receiving anti-ICAM-1 mAb (P < 0.0001), and 54.2 +/- 7.6 for rats receiving anti-LFA-1 mAb (P < 0.0001). The mean number of cells per milliliter of aqueous humor +/- S.E.M. was 1867.6 +/- 321.8 for controls, 21.7 +/- 5.3 for rats receiving anti-ICAM-1 mAb (P < 0.0001), and 295.1 +/- 71.2 for rats receiving anti-LFA-1 mAb (P < 0.0001). MAbs against ICAM-1 and LFA-1 significantly inhibited the development of EIU and were effective in treating clinically evident ocular inflammatory disease.

Animals

Effects of topical FK506 on endotoxin-induced uveitis (EIU) in the Lewis rat.

FK506 is a macrolide antibiotic and a potent immunosuppressant. To investigate the effect of topical FK506 on acute ocular inflammation, we evaluated its action on the development of endotoxin-induced uveitis (EIU). At two different concentrations of 0.05% and 0.3%, topical FK506 was applied to Lewis rats with EIU. In aqueous, the mean number of inflammatory cells per microliter +/- SEM was 2,389 +/- 1,277, 1,571 +/- 1,562, 898 +/- 882, and 69 +/- 152 for rats treated with vehicle alone, 0.05%, 0.3% FK506, and 1% prednisolone acetate. The median of histological grades was 2, 1.5, 0.8, and 0.5 for animals treated with these 4 different regimens respectively. Analysis of aqueous protein showed a small reduction in FK506-treated animals. Mean blood levels of FK506 were low in rats treated with topical FK506 (0.05%, 0.84 ng/ml; 0.3%, 2.0 ng/ml) suggesting that its therapeutic effect was not secondary to the systemic absorption of the drug. Although FK506 is not as effective as prednisolone, 0.3% FK506 produced significant decreases in the mean aqueous inflammatory cell number and histological inflammatory score as compared to control vehicle alone. We conclude that topical FK506 can suppress EIU in a dose-dependent fashion and may be an alternative medication for patients with anterior uveitis and contra-indication to topical steroid.

Administration, Topical

Diagnosis of reactive lymphoid hyperplasia by chorioretinal biopsy.

We treated a patient with reactive lymphoid hyperplasia in whom the diagnosis was made by chorioretinal biopsy. Histopathologic examination and culture of the biopsied specimen allowed us to rule out a neoplastic or infectious process. The biopsy result allowed us to treat him with systemic corticosteroid alone, thus avoiding the potential harmful side effects of other medications, including antituberculous drugs. There were no surgical or postoperative complications. This study confirms the usefulness of chorioretinal biopsy for establishing a diagnosis and formulating a rational treatment plan.

Antigens, CD

Combined cyclosporine and corticosteroid therapy for sight-threatening uveitis in Behçet's disease.

Behçet's disease is a multisystem disorder that may cause profound ocular inflammation and blindness. We reviewed 19 patients with severe ocular Behçet's disease treated with combined cyclosporine and corticosteroid therapy. Previous treatment with corticosteroids alone failed to control the uveitis in all patients. Ten patients were given cyclosporine therapy alone (mean dosage, 8.6 mg/kg of body weight per day), and nine patients were given lower dosages of cyclosporine (mean dosage, 6.2 mg/kg of body weight per day) in combination with prednisone (mean dosage, 29.4 mg per day). The mean follow-up on therapy was 51 months. After three months of therapy, a trend toward greater improvement in visual acuity was noted in patients treated with combined cyclosporine and prednisone compared to those receiving cyclosporine alone (17.8 letters vs 10.2 letters, P = .2379), but after one year little difference was observed in the improvement between the two groups (5.8 letters vs 3.3 letters, P = .7984). However, a trend toward greater renal toxicity was seen in patients treated with cyclosporine alone after both three months and one year of therapy. Because of either a suboptimal therapeutic response or adverse effects, all patients treated with cyclosporine alone at baseline had prednisone added to their regimen after a mean time of 23.5 months. Overall, visual acuity remained stable or improved in 28 of 37 eyes (75.7%) over the course of therapy. These data suggest that combined cyclosporine and prednisone therapy is an effective treatment for Behçet's uveitis and may be less toxic than therapy with cyclosporine alone. A prospective, randomized trial with a larger sample size is needed to provide definitive data.

Adolescent

Treatment of cytomegalovirus retinitis with an intraocular sustained-release ganciclovir implant. A randomized controlled clinical trial.

BACKGROUND AND METHODS: We performed a randomized controlled clinical trial to assess the safety and efficacy of a 1 microgram/h ganciclovir implant for the treatment of newly diagnosed cytomegalovirus (CMV) retinitis in patients with the acquired immunodeficiency syndrome (AIDS). Patients with previously untreated peripheral CMV retinitis were randomly assigned either to immediate treatment with the ganciclovir implant or to deferred treatment. Standardized fundus photographs were taken at 2-week intervals and analyzed in a masked fashion. The study end point was progression of retinitis based on the photographic assessment. RESULTS: Twenty-six patients (30 eyes) were enrolled. The median time to progression of retinitis was 15 days in the deferred treatment group (n = 16) vs 226 days in the immediate treatment group (n = 14) (P < .00001, log-rank test). During the study, 39 primary implants and 12 exchange implants were placed in immediate-treatment eyes, deferred-treatment eyes that progressed, or contralateral eyes that developed CMV retinitis. Postoperative complications in the total series included seven late retinal detachments and one retinal tear without detachment. Final visual acuity was 20/25 or better in 34 of 39 eyes. The estimated risk of developing CMV retinitis in the fellow eye was 50% at 6 months. Biopsy-proven visceral CMV disease developed in eight (31%) of 26 patients. The median survival was 295 days. CONCLUSION: The ganciclovir implant is effective for the treatment of CMV retinitis. Patients with unilateral CMV retinitis treated with the implant are likely to develop CMV retinitis in the fellow eye, and some patients will develop visceral CMV disease.

AIDS-Related Opportunistic Infections

A clinicopathologic report of the retinal lesions associated with didanosine.

Didanosine, a purine analogue with antiretroviral activity, is used in the treatment of human immunodeficiency virus disease. Associated toxic effects of didanosine include pancreatitis, peripheral neuropathy, and retinopathy. The retinal lesions associated with didanosine therapy were studied in a 6-year-old girl with acquired immunodeficiency syndrome. Gross examination disclosed multiple well-circumscribed depigmented lesions in the midperipheral retina. Microscopic examination of these lesions showed multiple areas of retinal pigment epithelial (RPE) loss, some surrounded by areas of hypertrophy or hypopigmentation of the RPE. Partial loss of the choriocapillaris and neurosensory retina were also noted in areas of diseased RPE. Transmission electron microscopy showed numerous membranous lamellar inclusions and cytoplasmic bodies in the RPE cells. These data show that didanosine primarily affects the RPE and that the choriocapillaris and overlying neurosensory retina are also dystrophic in areas of RPE loss.

Child, Preschool

gamma Interferon expression disrupts lens and retinal differentiation in transgenic mice.

We previously generated an animal model for the study of autoimmune diseases of the eye by targeting gamma interferon (gamma IFN) expression to the lens of transgenic mice. Here, we have studied the effect of constitutive lens expression of gamma IFN on eye development of these transgenic mice. By Day 18 of embryonic development, lens and retinal differentiation programs are completely disrupted; normal lens epithelia and fibers are replaced by balloon-like cells and retinal differentiation into inner and outer neuroblastic layers is already affected. The mRNA levels of gamma E- and/or gamma F-crystallin and MIP, markers of lens cell differentiation, are drastically reduced, while expression of ICSBP, a gamma IFN-inducible transcriptional factor, is induced in the alpha ACry-gamma IFN transgenic mouse eyes. Taken together, our results suggest that constitutive expression of gamma IFN and its induction and activation of gamma IFN-inducible transcriptional factors in the eye altered the developmental fate of cells destined to become lens fiber cells by altering the pattern of lens gene expression.

Animals

Corticosteroids enhance S-antigen expression in nonretinal ocular tissues of rats with experimental autoimmune uveitis.

S-antigen (S-Ag), a major protein on the retinal photoreceptor cell, can induce experimental autoimmune uveitis (EAU). We have previously detected S-Ag and its mRNA in irises of chronic uveitis patients receiving long-term steroid therapy. To further investigate the effect of steroid therapy on ocular tissue, we compared levels of S-Ag and its mRNA in EAU rats with and without steroid treatment. EAU was induced in 72 Lewis rats by two footpad injections of S-Ag. The rats were then treated with Depo-Medrol or phosphate-buffered saline by intramuscular injection. Eyes were collected at different time points. S-Ag mRNA was detected in the lens epithelium, trabecular meshwork, iris, and ciliary body of 47.2% of the steroid-treated group vs 22.2% of the controls. S-antigen was also detected in 30.6% of the eyes of the treated group vs 16.7% of the controls. S-Ag and its mRNA was found only in the retina of normal rats. These results support the hypothesis that prolonged corticosteroid therapy in uveitic patients might enhance the expression of S-Ag in nonretinal ocular tissues and might contribute to the ocular side effects of corticosteroid.

Animals

Toxoplasma gondii: acquired ocular toxoplasmosis in the murine model, protective role of TNF-alpha and IFN-gamma.

DNA and mRNA amplification by the polymerase chain reaction (PCR), immunohistochemical, and histopathology were performed in the eyes and brains from C57BL/6 mice infected with an avirulent strain of Toxoplasma gondii (ME49). Focal ocular inflammation and retinal pigment epithelial involvement were commonly observed after 15 days of infection. Four weeks after infection a stable number of cysts was observed in the brain but rarely in the eye, and they did not elicit an inflammatory response. In most of the ocular lesions the presence of the parasite could not be demonstrated even with the PCR technique. B1 DNA fragments of T. gondii were detected in only 4 of 11 eyes tested by PCR and Southern blot hybridization. Treatment of mice with mAbs against T cells (CD4 plus CD8) or cytokines (IFN-gamma or TNF-alpha) resulted in a marked increase of ocular lesions, more often associated with the presence of the parasite and the severity of inflammatory response. This model and the techniques utilized here can improve our understanding of the respective roles of parasite proliferation and immune mechanisms involved in the pathogenesis of acquired ocular toxoplasmosis.

Animals

Experimental melanin-protein-induced uveitis in the Lewis rat. Immunopathologic processes.

PURPOSE: To study the immunopathology of experimental melanin-protein-induced uveitis in the Lewis rat. METHODS: Rats were immunized with bovine ocular melanin protein. The kinetics of experimental melanin-protein-induced uveitis was studied by clinical examination and immunopathology. Cellular and humoral responses were evaluated by lymphocyte proliferation, delayed-type hypersensitivity, and agglutination. After clinical disease subsided, recurrent experimental uveitis was induced with a low-dose footpad injection of lipopolysaccharide. RESULTS: Experimental melanin-protein-induced uveitis was characterized by bilateral uveal infiltration mainly with lymphocytes and monocytes. Delayed-type hypersensitivity, lymphocyte proliferation, and agglutination to bovine ocular melanin protein were positive. Expressions of major histocompatibility complex class II and intercellular adhesion molecule-1 were observed before ocular infiltration. The predominantly infiltrating cells were CD4+ lymphocytes. Experimental melanin-protein-induced uveitis subsided within 1 month, spontaneously recurred within 1 week in approximately one quarter of the rats, and was inducible in most rats with 5 micrograms of lipopolysaccharide confirmed by histopathology. CONCLUSIONS: Experimental melanin-protein-induced uveitis is a T-cell-mediated autoimmune uveitis, resembling noninfectious recurrent iridocyclitis and choroiditis in humans.

Animals

Retrovirus-mediated gene transfer and expression of human ornithine delta-aminotransferase into embryonic fibroblasts.

Ornithine delta aminotransferase (OAT) is a nuclear-encoded mitochondrial matrix enzyme that catalyzes the reversible transamination of ornithine to glutamate semialdehyde. In humans, genetic deficiency of OAT results in gyrate atrophy of the choroid and retina, a blinding chorioretinal degeneration usually beginning in late childhood. This disorder has been shown to be autosomal recessive, and is often caused by missense, nonsense, and/or frameshift mutations in the OAT gene. With the view of applying gene therapy, a Moloney murine leukemia virus (MoMLV)-based recombinant retrovirus vector has been constructed. The human OAT cDNA was placed under the control of the enhancer-promoter regulatory elements derived from the MoMLV long terminal repeat (LTR). The construct was transfected into the retroviral packaging cell lines GP + E - 86 and psi CRIP to produce virus particles. Supernatant from these OAT retrovirus producer cell lines were used to transduce mouse C57B1/6 embryonal fibroblasts. We showed that the recombinant retrovirus transfers the OAT gene to the recipient cells, which produce an OAT RNA transcript when analyzed by Northern blot. Western blot analysis and enzymatic assays confirmed the presence of an OAT polypeptide that has a high enzymatic activity in the transduced cell lines, even after a long period of time in vitro.

Animals

Review: implants.

An implantable sustained release device has been developed to treat chronic disorders of the eye. The device, consisting of a central core of drug encased in layers of permeable and impermeable polymers, can be implanted subconjunctivally or intravitreally. This technique was used to develop a ganciclovir device which, when implanted into the vitreous, maintains therapeutic vitreous levels of drug for 8 months. Initial studies in patients with cytomegalovirus (CMV) retinitis indicate that this treatment may offer better control of the disease and fewer side effects than existing therapies. Cyclosporine A devices were prepared for the treatment of uveitis. Early data suggests that these devices maintain therapeutic levels in the vitreous for approximately 3 years. Work on efficacy and toxicity is continuing. Although clinical applications of these devices are likely to be restricted to diseases requiring chronic drug therapy, they can be used to investigate optimal delivery rates. Subconjunctivally implanted devices releasing 5-FU for 12 days maintained filters in cynomolgus monkeys for 3 months. Similar devices maintained low intraocular pressure in 75% of high risk filter patients.

Animals